A Grief Observed
by exorcisingemily
Summary: How do you cure a Knight of Hell who doesn't want to be saved? Dean/Castiel, Season 10. Demon!Dean


_God has not been trying an experiment on my faith or love in order to find out their quality. He knew it already. It was I who didn't. … He always knew that my temple was a house of cards. His only way of making me realize the fact was to knock it down._  
― C.S. Lewis, A Grief Observed

Castiel knows before Sam does, and God how he wishes he didn't.

"Rumors of my death have been greatly exaggerated." Dean's left-hand smirk still tugs his lips up distractingly, amusement lighting green eyes that Castiel has memorized the precise shade of over years of silent conversations given in glances and glowers, prolonged staring and lingering gazes. They're just as familiar, but they're wrong now as he meets Castiel's shocked stare past Sam.

Dean's hand is still on Sam's shoulder, the younger Winchester stays half caught in his brother's embrace that Castiel interrupted, his long frame stooped and staggered by his relief and shock, still too surprised to process onwards from there fully. He watched his brother die, and once more against the odds, Dean is back for him. It's clear that Dean's return from death just happened, that he laid dead for hours after their return, and then found his brother here in the basement only moments before Castiel reached them.

Sam thinks Castiel did this, Cas realizes with a chill. He has faith that this is one last miracle from their guardian angel; but even if he still had the power to right this, Castiel was too late. He's always too late. He came as quickly as he could, drove without stopping to reach his friend and to see the truth for himself, but by the time he found them in the Bunker, Dean has risen like Lazarus from the pit once again.

"Sam." There's a warning in Castiel's voice, and Dean's lips twitch into an easier smile even as he shakes his head out of Sam's line of sight, teasingly shushing Castiel. Phantom scars seem to twist his face in after-image, turning his expression into a rictus grin of sharp teeth and flayed flesh, and that more than the request for silence draws Castiel up short.

Castiel has spent years watching Dean; it's suddenly a struggle to make himself even look at him, now.

Maybe that's what gives Dean away, more than anything. Sam's a Winchester, born and raised into suspicion even of (or perhaps especially of) the people he cares about most. A furrow creases his expressive brow when Castiel turns his head away, hazel eyes narrowing and movements slow to keep Dean from being alerted as Dean watches Castiel in apparent fascination. The holy water from Sam's jacket pocket hisses as he pours it over the hand on his shoulder. He's nearly as quick to his knife as Dean is to clear across the room away from him, snarling under his breath as the ever-present rage makes his voice deep and rough, temper flash boiling with the steam rising from his skin.

"Son of a _bitch_." Dean shakes his scalded hand out as he snaps his chin back up to cast a glare at them with eyes gone black. "The hell did you go and do that for, Sammy?"

"You're not my brother." Whatever grip Dean has on his former humanity seems to snap at that accusation as he stares down his younger brother, the vestiges of his humor draining away. Castiel isn't sure Dean even realizes his hand is curling around the First Blade beneath the hem of his jacket as if he's seeking out reassurance and comfort from it, upper lip drawing back in a faint sneer.

"Not brothers, huh? Heard that one before."

The jab is well placed, Sam's guilt is still fresh on his mind, but he's determined. Sam looks at him and sees something possessing his brother's body, parading Dean's corpse in front of him and giving him false hope before snatching it cruelly away. He doesn't understand yet how much worse things are than that. "Exorcizamus te, omnis immundus spiritus. . ."

"_Sam_." Castiel's hand falls hard on Sam's shoulder, drawing the hunter back behind him, unconsciously protective in a way that makes Dean smirk, watching him as if he's learned a fascinating new trick. After the first Latin words of the ritual roll past without harm, Dean leans back against the wall behind him, shoulders to the concrete, arms folded across his chest and ankles crossed at his boots, seemingly unconcerned, though his hand never strays far from the hilt of the blade.

(There's still blood on his shirt. Castiel stares at it, rather than at Dean's face, waiting for Sam's words to die out, for silence to fall between them all again.)

"You done?" It's achingly familiar, reminiscent of Dean's impatience with Sam or Castiel's 'nerdy' tendencies, but jeering this time, the anger from Sam's declaration that they're not family obviously still keeping him furious. It's easier to imagine he's hurt and angry than to consider the alternative that Dean just doesn't care anymore.

"Who the hell are you?" Sam demands, fingers flexing on the handle of the demon blade. Denial is a blinding force, but it has to be a comforting one in its way. It's simple to look at Dean's black eyes, his smug expression, and just see a stranger. It's worse when he blinks the darkness away, green eyes sliding towards Cas as he gestures at him.

"You wanna field this one, Cas, or you just gonna keep saying _his_ name all meaningfully?" He's definitely mocking Castiel, and it would be easier if his eyes didn't crinkle when Castiel's gaze snaps back up to his face. Castiel's jaw bunches, chin jutting angrily, and Dean's grin just widens like he's sitting in the driver's seat laughing to himself as he makes a joke or reference Castiel never used to understand. "He isn't gonna believe shit that I say to him."

"This is Dean." Castiel rumbles, and he watches the sickening slide of the demon's face superimposed over whole flesh, his voice steady and his shoulders square even when he feels vaguely nauseated. He doesn't know any other way than to give the bald truth, but he won't show weakness to the demon in front of him. "There is nothing possessing him, this is your brother. A demon."

Sam's response is immediate and vehement. "Bullshit."

"Oh, come now Moose. You're supposed to be the smart one. That denial is only going to stretch so far." The glass clinks as Crowley fills it from the bottle, raising it and taking a whiff of alcohol before wrinkling his nose in distaste, ignoring the tension caused by his abrupt and unannounced arrival. "If you're stewing your brain in this swill no wonder you're a little slow." He drops the drink back onto the table, addressing Sam once again. "You should be proud, Sam. Your brother's been promoted. All grown up and a Knight of Hell. The health benefits are a _miracle_."

Crowley's voice abrades Castiel's already frayed nerves, and he can't help himself from turning toward the King of Hell as he smiles genially at Sam. In their years of grudging alliance, their times as each other's greatest enemies, through Crowley's manipulation of his pride, Castiel has never seen Crowley for anything other than he was: one of the worst kinds of demon, dedicated to tempting and turning humans and angels alike away from God. It's easy for Castiel to hate him.

They're bracketed by Hell's most powerful demons on either side, now, and some clinically detached portion of Castiel's subconscious has calmly informed him that he has no possible way of surviving this encounter, even as his blade drops into his fist, bringing with it purpose.

Impulsiveness is a human trait. A Winchester trait, one that doubtless contributed to this mess to begin with. It's easy to lunge, but harder to move once Sam's got a hold of his arm in both of his. It shouldn't slow him down, shouldn't foul his shot, but it does.

The blade clatters to the concrete as Castiel hits the wall, Sam skidding to a halt at his feet, caught alongside Castiel in the wave of force from a simple dismissive flick of Crowley's wrist. The impact leaves Castiel winded, catching himself with a hand braced on his knee and stolen grace burning in him, a useless expenditure of what little he has left, in a display that he can't bluff Crowley with this time and can't sustain. Contrary to his obviously weakened state, his words are the stentorian accusation of God's once fearsome warrior.

"_You_ did this."

"And by 'this' you mean me?" Dean's drawl surprises Castiel, makes him freeze in the act of hauling himself to his feet again, caught by how close Dean's voice is and how amused. He flinches when Dean steps before him and stoops down to his level, elbows on his knees and Castiel's blade dangling loosely from his hand, reflective in the angelic light gathering around him. Even now, Castiel can't risk injuring Dean, and he feels sick again when suddenly dimming the display of grace earns him a knowing wink. "That's what this is all about, right?"

_Ultimately, it was all about saving one human, right?_

No, not _now_. After everything they've been through together, Dean can't acknowledge this_ now_.

Cas expects Crowley's mocking rejoinder about jealousy, about how he's not 'doing' anything with Dean. He expects the quick look of sympathy he gets from Sam as the hunter pushes himself to his feet again, still at a loss for what to do with the idea that Dean is a demon. But Castiel couldn't have prepared for Dean sliding an arm around him and pulling him to his feet again with all the easy familiarity of dozens of times propping each other up, combined with a hand that lingers too long.

Dean _knows_. He knows, and now without inhibitions he's already using what he knows against Castiel.

Crowley is still speaking to Sam, but Castiel closes his hand around the returned sword and forcibly shrugs Dean's hand of him, eyes sliding away from Dean again. Dean raises his hands in mock surrender, showing he has taken them away from Castiel entirely, but doesn't step back.

Dean's placed himself between his brother and his angel and Crowley, a barrier of sorts in the wake of Castiel's attempt to kill Crowley, and Crowley's telekinetic counter. Castiel doesn't know what to think of that positioning, and clearly neither does Sam.

Is he protecting them, or Crowley?

" . . . Dean?"

Sam still doesn't want to believe it, that's clear in his voice and his stance, in the uneasy way he looks at his brother as though he's expecting Dean to either attack them or drop dead again. Dean turns his head without moving, watching his brother flatly.

"Yeah. I'm me." Dean takes an unnecessary breath and then grins again, but it doesn't reach his eyes (they're green but dead inside, and Castiel grinds his teeth and refuses to look). "What, you gonna start acting like black eyes is a new thing in this family, Sam?"

Friend or enemy, Dean Winchester is the most damaging threat to Sam and Castiel alike. Sam gapes at him a moment, wounded, and Dean doesn't flinch back from an expression that in years past would have sparked apologies or brotherly protectiveness.

"You didn't. . . How are you a demon? Even with the blade, you haven't been gone long enough for Hell to. . ."

Dean shrugs as if it doesn't matter, but his arms fold again and it puts his hand near the blade. "Been there. Done that. Woke up this way. Got the sales pitch. . ."

"And now we really should be going." Crowley's growing impatience with the family drama playing out before him is apparent. Unintimidated by Castiel's continuing glare, unmoved by Sam's horror, he addresses Dean like he's the only person in the room. "Hell is. . ."

Dean turns towards him, a finger to his lips, and Castiel can feel the power raising the hairs on the back of his neck, heat rolling off of the man in front of him making the room swelter. Sam takes a step back again in surprise: it's the first time he's understood that, even as cutting as his comments have been, Dean is _holding back_. There's rage in him, and with a practiced draw the First Blade sits in his hand like an extension of his arm, pointed at a forcibly silenced Crowley from across the room, his words a snarl.

"I don't take orders from you. I am no one's _mindless attack dog_." There's something to the words that sounds like a denial of an accusation left to fester too long, one of the many slights Dean used to carry with him, internalize, and struggle with when he was a human. "You wanna live, you leave. I just got fucking stabbed to death, and I want to kill something right now. You're the person in this room I least give a shit whether you live or you die, and you're pissing me off."

Dean is taking to the power in him too quickly; a damaged, humanity-free version of a man who has never been a stranger to violence. Across the room, Crowley seems to come to the same conclusion, shrewd stare fixed on Hell's new knight as he mimes zipping silent lips sarcastically before he completes the gesture with a snap, the sulfuric smell of demon thick in the room with his disappearance. Castiel has no doubt that he'll find Dean again soon, bend his ear once Dean has slaked his bloodlust.

"…So you do care if we live or die." Sam's trying to grab onto something, anything, to let him know how much of Dean is still in there.

Dean doesn't answer him. Fingers opening and closing on the blade, he seems distracted as he stares after Crowley as if he isn't sure he should have let him go. As if he needs to kill something now. It's instinct to reach out, to rest a hand on Dean's shoulder and try to ground him, but Castiel's hand falls back to his side before he can make contact, as Dean rounds on them.

"Where's Gadreel." It's a demand and an accusation. Castiel draws himself straight and meets Dean's challenge, shaken out of his thoughts. When he's holding the blade the demon in Dean is stronger, clearer, and it's harder to see the man he knew in the face beneath.

"Dead."

Dean grunts, but it's impossible to tell if he cares how Gadreel died.

"Metatron?"

"No longer your concern." Even Sam bristles at that declaration, and Castiel can't blame him . . . but it's worse with Dean. Dean has always been taller than him in this vessel, but he's only rarely felt as if Dean was looking down on him, and never before like this. Their long ago lessons in personal space never entirely took between them, but even so it's unsettling to have Dean so close to him now, bracing the fist holding the First Blade against the wall beside Castiel's ear, bracketing him in, forcing him to look up at Dean's true face as it twists, monstrous and scarred.

"Douchebag put a fucking sword through my heart, Cas, don't you I think I'm owed a little payback?" It's not the sentiment that's disturbing, it's the delivery. Another step closer, and Castiel would have to choose between letting Dean press him into the wall, or using the sword still uselessly in his hand. Dean is leaving him that choice, nearly daring him: he knows Castiel's weakness now, the way Uriel did, Zachariah, Crowley, Raphael, Naomi, and now Metatron. He also knows he can use it more directly than any of the others before him.

"Cas, he's got a point. . ." Sam is agreeing with Dean, but he believes it's partly a distraction. Castiel tries not to track Sam's movement, and that leaves him staring up at Dean, forced to meet his eyes.

Forty years, Dean spent in hell before Castiel could reach him, another angelic scheme to break this man, to bend him into a role. Heaven wanted him as a weapon, hollowed out for Michael to use once they shaped him properly. Crowley cast him as a knight, a general for a destabilized Hell. Metatron wrote him as the love interest in Castiel's story, lured across the country with obvious clues and then brutally killed to cripple Castiel. At the time, Metatron didn't know about the first blade, or the mark. . . he just knew that Castiel needed Dean to function. Cas knows in the coming days he's going to hate himself for his own role in trying to use Dean, to reduce him to a weapon in his own wars. . .

But none of that is Dean, none of it takes the man himself into account. He's still in there, all of him: damaged and mutilated by outside forces, yes, but struggling to beat a curse that is far older than him, and theoretically stronger than any one man could hope to control.

But that's what Dean does.

"Metatron killed me, Cas." The emphasis is there the way Castiel knew it would be, poisonous and tempting at once, trying to pull Castiel into responding to him. ". . . He killed _me_, and what, you're gonna protect him now?"

"No." Sam's in place. Taking a bracing breath he doesn't need, one that smells of blood and Dean and sulfur, Castiel ignores the demon to speak to the man. "I'm going to protect you."

The movements are almost too quick to follow. Castiel's hand snaps out, closing over Dean's wrist and shoving it backwards towards Sam and the spell-scored handcuffs he retrieved, but Dean's fingers immediately curl around Castiel's hand beneath the sleeve of his jacket and the teeth of the First Blade barely miss Castiel's face as Dean twists to snatch the open circlet of the cuff, stronger than the angel as he manhandles him into place, off-balancing him into Sam with a shove.

In the end, Dean stands over his brother and the angel where he's handcuffed them together, dragging in breaths like he's mid-fight, dangerous and unhinged, a tremor running through his hand where he still holds the blade.

"Dean, man, you gotta. . ." Sam struggles to get his long legs under him, and just as quickly it's as if he's smacked back down by an unseen hand, forced to stay down in a sprawl, the lights above them flickering. It doesn't stop his entreaty to his brother. "This is the blade and the mark. We can cure you, okay? Just put down the blade. You don't have to be this. . ."

Dean doesn't move as Castiel pushes himself to his feet, clasping wrists with Sam to pull the hunter up with him against the press of Dean's power, and Dean allows it this time. The lights of the basement pop and sway madly, playing over Dean before him. It's morbidly fascinating, and Castiel can't tear his eyes away—shadows and light, Dean's handsome features or the twisted true visage of the demon he's become, eyes black or green, everything about him is contradictory, dizzying, every shift in the swaying lights redefining him in the angel's vision as he lets Sam try to reach Dean.

"You told me you never wanted to be this, Dean. . . let us help."

A lifetime ago now the angel Castiel laid siege to hell, filled with purpose and conviction, convinced he was intended by God to save the man before him. He had been too late to save him suffering, to keep him from breaking, and he didn't yet realize that they'd never intended him to lift Dean out unscarred. Heaven needed Michael's vessel to be pliable to them, and Castiel expended too much of himself into healing Dean, into pulling him back from the brink of . . . this.

This is his failure, staring him in the face as if forty years of war in Hell, and his sacrifice on Heaven and Earth and Purgatory to protect this man, had never happened at all.

"I am this, Sam. And you know what. . . .? It feels _good_." Dean slowly tucks the blade away, reverential in his treatment of it and completely disregarding the two of them as a threat any longer. "I don't need your damn help, or your protection." The last word is to Castiel, a faint note of scorn in his voice as he glances at the diminished angel briefly, as if pointing out that there's little Castiel can do for him now. "I'm not gonna let you be the frikkin' Abel to my Cain, Sam, and you're sure as hell no Colette, Cas. You get near me, all it's going to do is get you two killed." Dean's finger jabs out, pointing at them both as he issues a final command. "So, you want to help me? Stay out of my way."

Then he's just… gone.

It feels as if all the air is sucked out of the room in Dean's departure, a void left behind where he once stood. There should be more to mark his passing, some physical manifestation of the devastation left in his wake. All that's left is silence; a shattered man and a dying angel blinking in the suddenly restored light.

Sam lets his breath out in a broken curse, trying to lift his hands to his face to scrub away evidence of his misery, but the motion drags Castiel's hand limply up with his by the cuffs, reminding him of the restraint and that he's not entirely alone in this. As Sam leads them to the table to unlock the cuffs, Castiel picks up the discarded whiskey and foregoes the glass touched by Crowley, closing his eyes and swallowing it down until his throat burns, until the bottle runs empty.

He's lost enough grace that he should be able to feel it, soon. At least then he'd feel something.

He wasn't meant for this, isn't built for it. He reshaped his millennia of existence around one man, and never let himself consider how very fragile that foundation would be. From Metatron, Castiel was 'blessed' with millions of depictions of grief, an endless array of authors and films that attempted to explain this most human suffering. They all fall short. No carefully chosen words or quotes or dramatic scenes can begin to touch the cold settling over him.

His eyes narrow, grabbing ahold of a thought before it can slip away, turning it over in his mind and attempting to find traction again. Frowning faintly, Castiel checks back in mentally to see Sam pacing before him, hands tangled in his long hair.

"What're we going to do, Cas? We need him back here if we're going to cure. . ."

References. Every book and movie in his mind, and he can't turn up something to explain Dean's words. It's a clue, something to research, something Dean knows that Castiel and Sam do not.

"Who's Colette?"


End file.
